module Component.Button
  ( ButtonIn(..)
  , buttonInDefault
  , ButtonOut(..)
  , button
  ) where

import qualified Data.Map   as M
import           Data.Text  (Text)
import qualified Data.Text  as T
import           Reflex.Dom (Dynamic, Event, MonadWidget)
import qualified Reflex.Dom as R

import qualified Icon

data ButtonIn t m = ButtonIn
  { _buttonIn_class   :: Dynamic t Text
  , _buttonIn_content :: m ()
  , _buttonIn_waiting :: Event t Bool
  }

buttonInDefault :: forall t m. MonadWidget t m => ButtonIn t m
buttonInDefault = ButtonIn
  { _buttonIn_class = R.constDyn ""
  , _buttonIn_content = R.blank
  , _buttonIn_waiting = R.never
  }

data ButtonOut t = ButtonOut
  { _buttonOut_clic :: Event t ()
  }

button :: forall t m. MonadWidget t m => ButtonIn t m -> m (ButtonOut t)
button buttonIn = do
  dynWaiting <- R.holdDyn False $ _buttonIn_waiting buttonIn

  let attr = do
        buttonClass <- _buttonIn_class buttonIn
        waiting <- dynWaiting
        return $ if waiting
          then M.fromList [("type", "button"), ("class", T.intercalate " " [ buttonClass, "waiting" ])]
          else M.fromList [("type", "button"), ("class", buttonClass)]

  (e, _) <- R.elDynAttr' "button" attr $ do
    Icon.loading
    R.divClass "content" $ _buttonIn_content buttonIn

  return $ ButtonOut
    { _buttonOut_clic = R.domEvent R.Click e
    }

-- mergeAttr :: Map Text Text -> Map Text Text -> Map Text Text
-- mergeAttr = M.unionWithKey $ \k a b ->
--   if k == "class"
--     then T.intercalate " " [ a, b ]
--     else b